Significant association of HLA-Bw4 with isoleucine at amino-acid position 80 (HLA-Bw4-80I) was found in the HLA-B*51− German cohort of BD patients [pc = 0.0042, OR = 2.35, 95% CI 1.41 to 3.93) and in the Turkish patients in comparison to the respective controls [p = 0.025, OR = 2.17, 95% CI 1.09 to 4.31]. The gene discussed is HLA-B; the disease is Behcet disease.